Brisbane completed a major AFL trade coup on Monday, signing up Geelong’s Allen Christensen for pick No.21.

Christensen, a talented midfielder who played in the Cats’ 2011 premiership side after being drafted in 2009, wanted to join Brisbane for personal reasons.

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The Lions were satisfied with the results of Christensen’s medical and the two sides lodged paperwork on Monday afternoon.

The Cats were happy to accept the somewhat lopsided deal for a 23-year-old that has played 65 games and will soon be entering the prime of his career.

“There were many things involved with Allen’s situation and we just had to help him as much as possible,” Geelong football manager Neil Balme said.

“The club is thankful for Allen’s contribution during his five years at the Cats including his part in the 2011 premiership side.”

Lions recruiting chief Peter Schwab was thrilled with the acquisition.

“Allen is a fantastic player who brings some good finals experience to our young list,” Schwab said.

“He offers a great injection of pace into our side and will be a valuable addition to our side.

“Leppa (coach Justin Leppitsch) spoke at the end of the season about a desire to recruit A-grade talent to our football club, and that is exactly what Allen is.”